~ RAINFALL AND DISCHARGE OF THE MURRAY RIVER. LXXV. 
connection with the investigations respecting rainfall and 
run-off of the Murrumbidgee catchment at Gundagai. The 
diagram (Appendix ‘“‘H’’) and following table shows the 
result of the calculations for the years 1894 to 1902 inclu- 
Sive, which period covers a high year and the lowest year 
on record. 
TABLE OF RAINFALL AND RUN-OFF OF THE DARLING RIVER 
AT WILCANNIA. Catchment area 235,000 square miles. 
eee ae 
charge of the M S a Mean rain- _Run-off 
Year. |qvacantia’ya| discharge | fect per |isllin inches] im inches / Tensentage 
megne ei in cusecs. jsquare mile catchment. | catchment. ! 
cubic feet. 
1894 | 253,644 8,043 0°034 26:81 0°464 1°73 
1895 60,234 1,910 0°008 19°53 0°110 0°56 
1896 87,733 2,782 0:012 21°14 0:161 0°76 
1897 70,199 2,226 0:009 18:94 0:128 0°67 
1898 57,049 1,809 0°008 15‘87 0°104 0°66 
1899 27,783 881 0°004. 16°04 0-051 0°31 
1900 69,474 2,203 0:009 16°33 0:127 0:77 
1901 32,167 1,020 0:004 15°71 0:059 0°37 
1902 710 22 0:0001 py =< 0:001 0:01 
Effect of abnormal drought of 1902.—From the above 
figures it will be seen that during the year 1894 the mean 
rainfall was 26°81 inches, of which only 1°73 was discharged 
or 0°034 second feet per square mile. The great drought 
culminating in the year 1902 was unparalleled in the 
history of Australian hydrology, and was responsible for 
the Darling River becoming a mere chain of water-holes. 
The rainfall over the Darling catchment for that year 
amounted to 11°22 inches, of which 99°99% was entirely lost 
by evaporation and other causes. When one realises the 
vast extent of the gathering ground of the Darling River 
at Wilcannia, an area one and a quarter times the size of 
France, it is difficult to imagine so smalla run-off. If half 
the rain that fell during 1902 reached the river channel, 
and passed the Wilcannia gauging station, it would have 
resulted in a mean discharge throughout the year of 97,120 
cusecs, or 4,415 times the amount actually discharged. 
